Re: Flow vs hp
Posted: Fri Oct 27, 2017 5:15 pm
I agree. That's close to the power per inch that Glidden was making with the small block in Pro Stock - but a much shorter stroke and lots of rpms.
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The possibility of getting to 1100 hp NA with the combination you're talking about, well it's probably about zero. You're talking about almost 3 hp per cfm. which is, at least to my knowledge, better than NHRA Pro Stock. A strong number for a really well built small block in that mid 400 ci. range you're talking about with pretty efficient inline valve heads and a single 4bbl and sheet metal intake is about 2.2- 2.3 hp/cfm. My reference is a little bit dated so more advanced valvetrain may slightly improve that but by hundredths, not tenths.Steve.k wrote: ↑Fri Oct 27, 2017 3:22 pm Well heres the deal. As most of you notice im a huge fan of the iron cleveland. Im also going to receive soon a cgi version of the Trackboss block. Ive been wanting to put together a heavy hiiter iron motor. I've got a set of early prostock heads from Paul JENKINS of florida. I flowed the early heads and on our bench they were in 350cfm range. Since then I've done work on another set and have them sitting in the 368 range. Some guys claim to hit over 400 but I've never seen the sheets so who knows. Anyhow whats it going to take or is it possible. We would be able to hit close to 450 cubes.
EngineTech1 wrote: ↑Fri Oct 27, 2017 6:30 pm
The possibility of getting to 1100 hp NA with the combination you're talking about, well it's probably about zero. You're talking about almost 3 hp per cfm.
That’s about the most absurd thing I’ve seen posted on this forum. Why exactly do you think people who develop cylinder heads use a flow bench? There’s a very real correlation between the two.joe 90 wrote: ↑Fri Oct 27, 2017 8:17 pmEngineTech1 wrote: ↑Fri Oct 27, 2017 6:30 pm
The possibility of getting to 1100 hp NA with the combination you're talking about, well it's probably about zero. You're talking about almost 3 hp per cfm.
no it's not.
CFM which an engine consumes as it runs is completely different from the imaginary CFM which it flows on a flowbench at 28 inches of water.
There's zero relationship between the 2 CFMs.
wish we had a like button.joe 90 wrote: ↑Fri Oct 27, 2017 8:17 pmEngineTech1 wrote: ↑Fri Oct 27, 2017 6:30 pm
The possibility of getting to 1100 hp NA with the combination you're talking about, well it's probably about zero. You're talking about almost 3 hp per cfm.
no it's not.
CFM which an engine consumes as it runs is completely different from the imaginary CFM which it flows on a flowbench at 28 inches of water.
There's zero relationship between the 2 CFMs.
Joe,joe 90 wrote: ↑Fri Oct 27, 2017 8:17 pmEngineTech1 wrote: ↑Fri Oct 27, 2017 6:30 pm
The possibility of getting to 1100 hp NA with the combination you're talking about, well it's probably about zero. You're talking about almost 3 hp per cfm.
no it's not.
CFM which an engine consumes as it runs is completely different from the imaginary CFM which it flows on a flowbench at 28 inches of water.
There's zero relationship between the 2 CFMs.
Talk about a can of worms. When the dude got specific he has heads that flow less than 370 cfm and wants to build close to a 450 cid. V8 to make 1100 hp. Obviously those things you mentioned are the types of considerations that go into designing a port for a given application but based on this guys statements this isn’t a highly developed cylinder head.
[q This is more typically where i thought the heads would go. However i had seen talk of more away from this site. Thanks for imput everyone.
Not a complete waste of money but they do not predict the future. Kaase had a nice article a while back on Hemi vs. Wedge heads. It is worth a read or two. Basically his two heads flow roughly the same on the flow bench but the Hemi head makes a lot more power on an engine. So the flow number tells you part of the story, but it doesn't tell you the whole story. There is a quality of the flow which is important. Also the location of the flow, and the velocity of the flow. I'm sure there are other things such as turbulence and swirl and who knows what else.